Skeptic Tank Text Archive File

G A L A G A
=============
by Brian Murray
(brian@demon.csd.unsw.edu.au)
There are apparently many different galaga implementations, this one
happens to be mine. I don't know how I would identify my particular
boards, but I'll give as much as I can. (They were from a tabletop
if that matters). There are two boards, both with blue solder masks.
The top one (slightly larger) is the CPU board, has the 4 processors
and program EPROMS, and holds a small credit-card sized daughter
board that plugs into a 28-pin DIP socket near the EPROMS. It also has
'DG-09-2' silk-screened in one corner near the main connector. The bottom
board is the video board. It has a small 5 pin connector in one corner
for the video output signal, wired as follows :
(closest to corner of board) 1 - Red
2 - Blue
3 - Green
4 - Sync
5 - Video GND
Note in my game, this connector has had wires soldered straight to it
and these brought around and soldered to the main connector in the
positions shown below, and the monitor wired to this connector instead.
Galaga DIP switch settings. The following information has been copied
from wiretap.spies.com (original submission by z_morganrw@ccsvax.sfasu.edu)
but slight changes have been made to reflect my game.
There are two sets of DIP switches on the Galaga CPU board. I'll label them
SWA and SWB following the schematic. SWA is closest to the corner of the
board (located at 11C), SWB closest to the main connector (located at 11E).
Switch bank SWA sets the number of credits, lives and lives given at certain
scores. (This is identical to switch bank 6K as specified by
z_morganrw@ccsvax.sfasu.edu) :
SW1 SW2 SW3 (Coins per Credit)
--------------------------------------------
ON ON ON FREE PLAY (although this doesn't seem to work for me)
ON ON OFF 4 Coins 1 Credit
ON OFF ON 3 Coins 1 Credit
ON OFF OFF 2 Coins 1 Credit
OFF ON ON 2 Coins 3 Credits
OFF ON OFF 1 Coin 3 Credits
OFF OFF ON 1 Coin 2 Credits
OFF OFF OFF 1 Coin 1 Credit
SW4 SW5 SW6 (Bonus ships awarded.)
Began with 2, 3, Began with 5
or 4 fighters fighters.
----------------------------------------------------------------
1st SHIP 20000 1st SHIP 30000
ON ON OFF 2nd SHIP 60000 2nd SHIP 100000
AND EVERY 60000 AND EVERY 100000
-----------------------------------------------
1st SHIP 20000 1st SHIP 30000
ON OFF ON 2nd SHIP 70000 2nd SHIP 120000
AND EVERY 70000 AND EVERY 120000
-----------------------------------------------
1st SHIP 20000 1st SHIP 30000
ON OFF OFF 2nd SHIP 80000 2nd SHIP 150000
AND EVERY 80000 AND EVERY 150000
-----------------------------------------------
1st SHIP 30000 1st SHIP 30000
OFF ON ON 2nd SHIP 100000 2nd SHIP 100000
AND EVERY 100000
-----------------------------------------------
1st SHIP 30000 1st SHIP 30000
OFF ON OFF 2nd SHIP 120000 2nd SHIP 120000
AND EVERY 120000
-----------------------------------------------
1st SHIP 20000 1st SHIP 30000
OFF OFF ON 2nd SHIP 60000 2nd SHIP 150000
-----------------------------------------------
1st SHIP 30000 ONE SHIP 30000
OFF OFF OFF 2nd SHIP 80000 ONLY
-----------------------------------------------
ON ON ON NO BONUS SHIPS GIVEN WITH THIS SETTING
----------------------------------------------------------------
SW7 SW8 (Number of fighters to start with)
----------------------------------------------------------------
ON ON 2 Space Fighters
ON OFF 3 Space Fighters
OFF ON 4 Space Fighters
OFF OFF 5 Space Fighters
SWB is used for setting the difficulty of Galaga. Switches SW4, SW7,
and SW8 don't appear to do anything. (This differs slightly
from switch bank 6J as specified by z_morganrw@ccsvax.sfasu.edu) :
SW1 SW2
-------------------------------------------------
OFF OFF Rank "A" - Easiest level of play.
ON ON Rank "B"
OFF ON Rank "C"
ON OFF Rank "D" - Hardest level of play.
SW3
-------------------------------------------------
ON Some sort of test/debug mode, do not use
OFF Normal operation
SW5 (The "damn the phone's ringing" switch :-)
-------------------------------------------------
ON Freeze game
OFF Normal operation
SW6
-------------------------------------------------
ON Automatic rack advance (cheat mode).
OFF Normal operation